This invention relates to a safety net for use during building construction or the like, and more particularly, but not exclusively, relates to an improved safety net for the prevention of builders or workers falling through an opening in a multiple storey construction site.
Safety nets for use in the building industry are known and generally comprise a mesh net of relatively thin cords or the like attached at its perimeter to a metal frame. These types of nets are commonly used on the exterior of buildings underneath scaffolding to catch falling workers or building materials. Similar nets may be used inside buildings to cover openings in the floors, such as stairwells, whereby the metal frame is required to be securely attached adjacent the edges of the opening.
The metal frame of these nets prohibits the net being universally adaptable to openings of different sizes and configurations. Furthermore, the metal frame bordering the perimeter of the safety net can be bulky, difficult to install and provide an obstruction which workers may trip over.
Where the safety net comprises a mesh net bordered by a guide cable which is anchored to the metal frame, several problems arise. Firstly, a worker falling into the net may be injured by the metal attachments, which project into the space of the aperture and secure the guide cable to the metal frame. Secondly, where the guide cable breaks or fails, the safety net is rendered useless as there is nothing to support the safety net. Finally, a closely spaced mesh net may lead workers to believe that the net is safe to be walked across. Upon attempting to walk across the net the worker may fall or trip and be injured.
Similarly important is the inadequacy of current safety nets to provide means by which the net may be adjusted to accommodate differently sized openings. Safety nets which comprise a metal frame require the frame and/or guide cable to be adjusted, which is time consuming and difficult, in order to fit the dimensions of different apertures. Alternatively, construction companies may require a range of metal frame safety nets of predetermined size. However, this is costly.
Furthermore, current safety nets also fail to provide a means for the passage of workers and building materials through a portion of the net while the safety net remains in place and retains full structural integrity.
It is therefore desirable to provide a safety net which can be adapted to various aperture sizes and retains significant strength upon failure or release of one or more support attachments.
According to one aspect of the invention there is provided a safety net for an opening, said safety net comprising a plurality of straps in a grid arrangement, said straps consisting of seat belt webbing or similar material, and anchoring means for anchoring the ends of the straps to the perimeter of said opening.
Preferably, the anchoring means for the straps are adjustable to allow the net to be adjusted to fit openings of different sizes. In a preferred embodiment, the anchoring means may comprise a metal plate having a first anchor portion adapted to be secured around the opening by fixing means, such as screws or bolts, or the like, and a second portion which includes spaced slots through which the end of a strap is threaded, thereby providing a secure adjustable fastening. In one preferred embodiment, the second portion is hingedly connected to the first anchor portion of the anchoring plate.
In a further embodiment the anchoring means comprises a quick-release anchor in which the first and second portions are formed separately as first and second parts adapted to be releasably locked together. The second part may include an integrally formed lug. The first anchor part may include an aperture adapted to receive and releasably lock the lug of the second anchor part. Preferably, the lug and the aperture of the first anchor part are T-shaped. Furthermore, the first and second anchor parts may be adapted for substantially flush alignment when the first and second anchor parts are releasably locked.
The safety net may also include a gap in one corner or along one side of the safety net to permit the transmission of building materials or workers, e.g. via a ladder, between adjacent levels of a building or construction site. This gap may be enlarged without substantially affecting the strength and integrity of the net due to the use of seat belt webbing to form the safety net and the use of separate anchor points on the ends of each strap. The construction of the invention also assists to maintain an adequate strength of the safety net where some of the straps or anchors fail.